Experimental Physics and
Industrial Control System

"Szalata, Zenon M." <[email protected]> · Tue, 1 Jul 2008 13:40:34 -0700

Thanks Andrew,
Yes, I failed to provide the crucial piece of information, which is that the board for which I am writing the device driver does not have a DMA controller built in; the DMA controller on the MVME 6100 processor board is to be used.
Thanks again,
Zen 

-----Original Message-----
From: Andrew Johnson [mailto:[email protected]] 
Sent: Tuesday, July 01, 2008 1:35 PM
To: [email protected]
Cc: Szalata, Zenon M.
Subject: Re: Epics DMA for the MVME6100

Hi Zen,

On Tuesday 01 July 2008 14:44:52 Szalata, Zenon M. wrote:
> I need to add support for DMA data transfer to a device driver that I 
> am writing.  The processor is MVME6100, OS is vxWorks, and I am 
> writing the device driver using Epics OSI routines.  Has anyone 
> written DMA support for this combination? Thanks in advance,

There may be some confusion about your question because there's a fundamental piece of information we don't know about your device: does it have a DMA controller built-in on the VME card, or do you need to use the DMA controller on the VME interface chip on the MVME6100 board?

Till's answer describes an RTEMS driver for the on-board Tsi148 chip.  I have a vxWorks driver for the same chip which replaces the one available in the mv6100 vxWorks BSP that implements the same API as my other drivers for the
Universe-2 and VMEchip2 chips used on older MVME boards.

Mark is talking about the case where the DMA controller is on the device itself, which can be a relatively simple thing to do as long as you have your BSP configured to make the CPU's RAM visible from the VMEbus.

HTH,

- Andrew
--
Talk is cheap. Show me the code. -- Linus Torvalds

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System